Shuttle Mystery Cancels Launch, Chance For Close-up Look At Comet

November 5, 1996|By Seth Borenstein of The Sentinel Staff

CAPE CANAVERAL — Astronomers will likely miss a once-in-a-lifetime chance to probe the mysteries of comets because NASA managers Monday decided to delay Friday's launch of the space shuttle Columbia by at least a week.

The delay was prompted by NASA's own mystery: the cause of insulation burns in a space shuttle booster rocket. Two investigative teams performing more than 1,000 tests still do not know why 60 unusual grooves were burned in the insulation of a booster used to launch the shuttle Atlantis in September.

By the time engineers figure out the cause - possibly by Monday - it will be too late to launch Columbia in time to view the much-anticipated comet Hale-Bopp. By that time, Hale-Bopp will appear too close to the sun to be seen by a special ultraviolet telescope that was going to be released by Columbia. The comet, named after its two discoverers, is 300 million miles away.

Columbia's No. 1 mission is to release the telescope, which will spend two weeks circling Earth, looking at celestial bodies using a light wavelength that other telescopes or the naked eye can't see. The wavelength, called extreme ultraviolet light, has waves as small as one-tenth the size of visible light waves.

By measuring extreme ultraviolet light, scientists get data that will help them learn what inert gases exist in a celestial object, including more than 100 other than Hale-Bopp, said Mark Hurwitz, a researcher with the University of California's Space Sciences Lab.

When Hale-Bopp was discovered last year, NASA decided to put the comet at the top of its target list. Some astronomers say Hale-Bopp will be the comet of the century when it nears Earth next spring. April and May will be the best time to see the comet, when it may be as bright as the brightest star.

As viewed from Earth's orbit, the angle between Hale-Bopp and the sun keeps getting smaller. By Nov. 14 - the day before Columbia's tentative launch date - it will be too difficult to distinguish the comet's light from sunlight. Also, the nearby sunlight could damage the sensitive telescope.

Mumma and Hurwitz said they had hoped to learn more about how cold it was when the comet was created and what's in it. Comets helped shape the way planets formed and could have killed off species, such as dinosaurs, they said.

Hale-Bopp can be monitored again using ultraviolet light in February 1997, but NASA has no plans to deploy an ultraviolet telescope then because the agency will be too busy adding new instruments to the Hubble Space Telescope.

''It would be really, really frustrating to lose this opportunity based on an engineering slip, but the safety of people is pre-eminent,'' Mumma said.

Columbia's delay marks the third time in 17 months that NASA delayed a shuttle launch because of booster problems.

The insulation damage never endangered Atlantis' crew, and Columbia's boosters probably won't need to be fixed.